A few hours ago Japan introduced new anti-piracy legislation designed to clamp down on illegal file-sharing. The regime is one of the most draconian in the world. In most countries users are only targeted when they upload copyright-infringing material to other Internet users, but the new law's wording means that simply downloading unauthorized material could result in a jail sentence.

According to the Recording Industry Association of Japan and their IFPI affiliates, the Japanese music industry is in trouble. Unauthorized downloads eclipse those from official source by 10 to 1, and the market for downloads shrank by 16% last year.

This decline needs to combated, they insist.

After intensive lobbying by the music industry, in June this year Japan approved an amendment to its Copyright Law that would see downloaders of unauthorized music face stiff criminal penalties in addition to the civil remedies already in place.

The wording here is important. While in some countries downloading copyrighted media without permission is already illegal, it is usually the uploaders (distributors) of content that are targeted in so-called “3 strikes” style campaigns.

While Japan already has the legislative muscle to hit uploaders with up to 10 years in prison and a 10 million yen ($128,300) fine, this new legislation makes criminals of mere downloaders.

From today, knowingly downloading copyright infringing material can result in a two-year jail sentence or a fine of 2 million yen ($25,680). But there could be complications.

Tracking uploaders of infringing material is a fairly simple affair, with rightsholders connecting to file-sharers making available illicit content and logging evidence. However, proving that someone has downloaded content illegally presents a whole new set of issues.

On BitTorrent, for example, rightsholders would have to be the ones actually sending the infringing material to a file-sharer in order to know that he or she is downloading it. This scenario could cause complications, since rightholders already have permission to upload their own content, making the source a legal one.

But for the implications for ‘downloaders’ could be even more widespread. The generally tech-savvy BitTorrent user understands the potential for being targeted for sharing, but by making mere downloading a criminal offense it is now feared that those who simply view an infringing YouTube video could also be subjected to sanctions.

For some rightsholders though, even this kind of draconian regime isn’t enough. As reported in June, music rights groups including the Recording Industry Association of Japan say they have developed a system capable of automatically detecting unauthorized music uploads before they even hit the Internet.

But to do that they need to be able to spy on Internet users’ connections and compare data being transferred with digital fingerprints held in an external database. That can only be achieved with the assistance of Internet service providers who would be asked to integrate the system deeply into their networks.